The purpose of the study is to evaluate how cerebellar resection surgery may affect pain sensation and the way the brain "reads" pain signals. By measuring brain activity in children and adolescents following surgery, the investigators hope to gain valuable information about pain processing in the brain.

This study is designed to test whether cerebellar resection surgery affects pain pathways in the brain. To participate a participant must (A) have had a cerebellar mass surgically removed, or (B) are a healthy volunteer with no history of pain disorders or mental illness. The study will involve sensory testing and brain imaging using magnetic resonance imaging (MRI) Sensory testing will be performed using a tub of cold water, as well as a contact thermode capable of delivering hot and cold temperatures. MRI brain scanning uses magnetic fields and radio waves to give pictures of the brain without using radiation.

Inclusion Criteria for patients:

• Age 4-18 years old at the time of surgery
• Resection limited to the cerebellum
• Within 20 years of surgery
• Good physical health excluding symptoms directly related to cerebellar resection
• No cerebellar-mass directed treatment other than surgical resection

Inclusion Criteria for all subjects:

• Age 6-38 years old at the time of participation
• No paralysis/hemiparesis
• No motor deficits that would interfere with performance or required tasks (button press withdraw hand from water bath)
• English speaking sufficient to comprehend and provide assent with parental assistance or consent if over the age of 18
• Ability to complete MRI without sedation

Exclusion Criteria:

• Claustrophobia
• Significant medical (e.g. asthma, renal, cardiac, gastrointestinal or immunological) or brain- related disorders (e.g. seizures, autism, psychiatric conditions such as severe depression, psychosis)
• Metallic or magnetic implants that pose a risk to the participant or to the data quality
• Weight > 285 pounds (weight limit of the fMRI table)
• History of drug abuse or positive drug screen
• Positive pregnancy screen
• Use of antidepressants or anticonvulsants, excepting patient usage after resection
• Significant alcohol history (ingestion of 5 or more glasses (> 40 oz) of alcohol per week)
• Tattoos containing metallic ink on the neck, shoulders, upper arm and head (which could heat up in the scanner, and potentially cause blistering or burning)
• Cardiac pacemakers
• Aneurysm clips and other vascular stents, filters, clips or other devices
• Prosthetic heart valves
• Other prostheses
• Neuro-stimulator devices
• Implanted infusion pumps
• Cochlear (ear) implants
• Ocular (eye) implants or known metal fragments in eyes
• Exposure to shrapnel or metal filings (sheet metal workers, welders, and others)
• Participants that require anesthesia to complete an MRI scan
• Receipt of a medication via transdermal patch

Patients with cerebellar resection and healthy volunteers.